Project Title: Cost-effective Thermally Activated Building Systems to Support a Power Grid System With High Penetrations of As-available Renewable Energy Resources (DOE-EF0008677)

Principal Investigator: Dr. Jialai Wang, The University of Alabama (UA), Tuscaloosa, AL

Team Members:  Dr. Zheng O’Neill, Taxes A&M University; Dr. Hongyu Zhou, The University of Tennessee, Knoxville; Drs. Som Shrestha and Xiaobing Liu, Oak Ridge National Laboratory; Dr. Rusty Sutterlin, Sutterlin Technologies, LLC.

This study develops and demonstrates a novel thermally activated building envelope system that integrates Phase Change Material (PCM)-based Thermal Energy Storage (TES) and the hydronic activation into the building envelope, with a goal to reduce the energy cost for building operation as well as to support renewable energy sources (RES) for the power grid reliability, quality, resilience, and dispatchability.

The proposed thermally activated building envelope unit consists of a panel (which could be a panel used in wall, floor, ceiling, or foundation) integrated with PCM and a capillary network that allows water circulation inside the panel.  The capillary network embedded within the panel function as thermal exchanger, which can either cool the panel through circulating the chilled water or heat the panel through circulating the warm water. We envision that the proposed system will fundamentally transform the current building envelope system and associated control through the following innovations: Material Innovation (micro-encapsulation of low-cost PCM using cenospheres): a novel technique to integrate PCMs into construction materials (concrete) through encapsulating PCMs into low-cost, fire-retardant, and highly thermal-conductive hollow fly ash particles. Its cost is just one third of the existing PCM microcapsules. Subsystem Innovation (Integration of CenoPCM with hydronic heating/cooling): an innovative thermal active panel with capillary tubes, which functions as thermal energy storage unit using heat sink and source from solar-thermal collector and ground loop heat exchanger. System-level Innovation (Supporting power grid systems with high penetrations of as-available reviewable energy resources): a novel integration of the envelope panel with PCM and capillary network to support a power grid system with high penetrations of as-available RESs (e.g., solar and wind).

Primary energy savings anticipated to be achieved across the U.S. building stock is approximately 0.77 Quads (770 TBtus) in 2030.